feat: parser should not know about cmd anything

gitdiff/apply_test.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"io"
 	"io/ioutil"
-	"os/exec"
 	"path/filepath"
 	"testing"
 )
@@ -232,9 +231,7 @@ type applyTest struct {
 func (at applyTest) run(t *testing.T, apply func(io.Writer, *Applier, *File) error) {
 	src, patch, out := at.Files.Load(t)
 
-	cmd := exec.Command("echo", "hello")
-
-	fileChan, err := Parse(cmd, io.NopCloser(bytes.NewReader(patch)))
+	fileChan, err := Parse(io.NopCloser(bytes.NewReader(patch)))
 	if err != nil {
 		t.Fatalf("failed to parse patch file: %v", err)
 	}

gitdiff/parser.go

@@ -7,7 +7,6 @@ import (
 	"bufio"
 	"fmt"
 	"io"
-	"os/exec"
 	"strings"
 )
 
@@ -16,7 +15,7 @@ const commitPrefix = "commit"
 // Parse parses a patch with changes to one or more files. Any content before
 // the first file is returned as the second value. If an error occurs while
 // parsing, it returns all files parsed before the error.
-func Parse(cmd *exec.Cmd, r io.ReadCloser) (<-chan *File, error) {
+func Parse(r io.Reader) (<-chan *File, error) {
 	p := newParser(r)
 	out := make(chan *File)
 
@@ -28,10 +27,8 @@ func Parse(cmd *exec.Cmd, r io.ReadCloser) (<-chan *File, error) {
 		return out, err
 	}
 
-	go func(cmd *exec.Cmd, out chan *File, r io.ReadCloser) {
+	go func(out chan *File, r io.Reader) {
 		defer close(out)
-		defer cmd.Wait()
-		defer r.Close()
 
 		ph := &PatchHeader{}
 		for {
@@ -68,7 +65,7 @@ func Parse(cmd *exec.Cmd, r io.ReadCloser) (<-chan *File, error) {
 			file.PatchHeader = ph
 			out <- file
 		}
-	}(cmd, out, r)
+	}(out, r)
 
 	return out, nil
 }

gitdiff/parser_test.go

@@ -7,7 +7,6 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"os/exec"
 	"reflect"
 	"strings"
 	"testing"
@@ -503,9 +502,7 @@ Date:   Tue Apr 2 22:55:40 2019 -0700
 				t.Fatalf("unexpected error opening input file: %v", err)
 			}
 
-			cmd := exec.Command("echo", "hello")
-
-			fileChan, err := Parse(cmd, f)
+			fileChan, err := Parse(f)
 			if test.Err {
 				if err == nil || err == io.EOF {
 					t.Fatalf("expected error parsing patch, but got %v", err)
@@ -580,7 +577,7 @@ index ebe9fa54..fe103e1d 100644
 	}
 	for i := 0; i < b.N; i++ {
 		reader := io.NopCloser(strings.NewReader(inputDiff))
-		ch, err := Parse(&exec.Cmd{}, reader)
+		ch, err := Parse(reader)
 		if err != nil {
 			panic(err)
 		}